Flowey

After destroying the soul’s and nearly killing sans flowey fled to the ruins, being the first monster corrupted he had a full out feast on the young and weak, his life was perfect when hunting he grabs the victim and slowly breaks their bones enjoying every scream they make.

Flowey had no fears living in the ruins, with all the land he wants and all the prey he could kill he didn’t have a care in the world, but one day he saw toriel hiding in her home talking to dolls so flowey thought he could take advantage, of this and kill her but she left him a mark he would never forget.

While toriel was destroying the ruins flowey had to live on scraps, and for the first time in a long while he actually felt fear, but as the prey got less and less he knew it wouldn't be long before toriel will leave and she did and so, flowey took the role as top predator again but this didn't last long.

chara was alive again and she had a taste for blood, he knows if she doesn't eat he will be her dinner so he is on a constant search for prey, so if she eats he can live to see another day.